This invention relates to foamable pharmaceutical and cosmetic compositions.
External topical administration is an important route for the administration of drugs in disease treatment. Many groups of drugs, including, for example, antibiotic, anti-fungal, anti-inflammatory, anesthetic, analgesic, anti-allergic, corticosteroid, retinoid and anti-proliferative medications are preferably administered in hydrophobic media, namely ointment. However, ointments often form an impermeable barrier, so that metabolic products and excreta from the wounds to which they are applied are not easily removed or drained away. Furthermore, it is difficult for the active drug dissolved in the carrier to pass through the white petrolatum barrier layer into the wound tissue, so the efficacy of the drug is reduced. In addition, ointments and creams often do not create an environment for promoting respiration of the wound tissue and it is not favorable to the normal respiration of the skin. An additional disadvantage of petroleum jelly-based products relates to the greasy feeling left following their topical application onto the skin, mucosal membranes and wounds.
Foams and, in particular, foams that are substantially based on non-aqueous solvents are complicated systems which do not form under all circumstances. U.S. Pat. Appl. No. 20050031547 relates to stable oleaginous cosmetic or therapeutic foam compositions containing certain active agents, having unique therapeutic properties and methods of treatment using such compositions. The foamable carrier includes at least one solvent selected from a hydrophobic solvent, a silicone oil, an emollient, a co-solvent, and mixtures thereof, wherein the solvent is present at a concentration of about 70% to about 96.5% by weight of the total composition, at least a non-ionic surface-active agent at a concentration of about 0.1% to less than about 10% by weight of the total composition; at least one gelling agent at a concentration of about 0.1% to about 5% by weight of the total composition; a therapeutically effective amount of at least one active agent; and at least one liquefied or compressed gas propellant, at a concentration of about 3% to about 25% by weight of the total composition.
WO 00/09082 teaches an anhydrous cleansing composition for topical application to human skin, comprising an ionic surfactant, glycerine, propylene glycol and water insoluble benefit agents. According to the examples of WO 00/09082, the concentration of the ionic surfactant is in the range of 18-22%.
U.S. Pat. No. 6,765,001 comprises a composition, method of enhancing potency and method of delivering corticosteroids in a vehicle comprising two or more penetration enhancers selected from the group consisting of diisopropyl adipate, dimethyl isosorbide, propylene glycol, 1,2,6-hexapetriol, and benzyl alcohol; and one or more of the group consisting of solvents and emulsifiers.
WO91/11991 teaches an essentially non-aqueous and non-oily foamable composition, that can be used for rectal administration of pharmaceuticals, comprising a liquid polar polyol or polyol mixture, a pharmaceutically active ingredient and at least one foam stabilizing and emulsifying surfactant. However, this foam composition is associated with disadvantages and the purposes of the present invention are not attained (see comparative example below).
There remains an unmet need for improved, easy to use, stable and non-irritating anti-infective foam formulations, intended for treatment of dermal and mucosal tissues. Particularly, there remains an unmet need for improved, easy to use, stable and non-irritating anti-infective foam formulations, with unique therapeutic properties.